14-ID-04
Committee:
Title:
Infectious Disease
Update to Arboviral Neuroinvasive and Non-neuroinvasive Diseases Case Definition
I. Statement of the Problem
The recent introduction of Chikungunya virus to the Caribbean increases the likelihood of imported and
locally acquired Chikungunya fever cases in the United States. The proposed revision to the case
definition for arboviral neuroinvasive and non-neuroinvasive disease adds Chikungunya virus to the list of
nationally notifiable arboviral diseases in the United States.
II. Background and Justification
Arboviral diseases are a condition under public health surveillance. More than 130 arboviruses are known
to cause human disease including West Nile virus (WNV), St. Louis encephalitis virus, eastern equine
encephalitis virus, Powassan virus, and California serogroup viruses which are endemic in various regions
of the United States (US). Most arboviral infections are asymptomatic. Clinical disease ranges from mild
febrile illness to severe encephalitis.
Sustained transmission of Chikungunya virus was reported from St. Martin in December 2013. This is the
first reported outbreak of Chikungunya fever in the Americas. More than 3,000 confirmed and 15,000
suspect cases had been reported by March 31, 2014. The main vectors, Aedes aegypti and Aedes
albopictus, are also the primary vectors for dengue. With the large number of persons who travel from the
Caribbean to the United States, some will arrive infected with the virus. Since the vectors are endemic in
southern United States, local transmission is likely. Adding Chikungunya virus to the list of nationally
notifiable arboviruses will ensure standardized reporting of cases.
III. Statement of the desired action(s) to be taken: CSTE requests that CDC revise the current case
definition for Arboviral neuroinvasive and non-neuroinvasive diseases to:
1. Add Chikungunya virus to the list of arboviruses included in the case definition;
2. Add arthralgia to the list of symptoms
3. Utilize standard sources (e.g. reporting*) for case ascertainment for Arboviral Diseases. Surveillance
for Arboviral Diseases should use the following recommended sources of data to the extent of coverage
presented in Table III.
Table III. Recommended sources of data and extent of coverage for ascertainment of cases
of Arboviral neuroinvasive and non-neuroinvasive diseases.
Coverage
Source of data for case ascertainment
Population-wide
Sentinel sites
Clinician reporting
X
Laboratory reporting
X
Reporting by other entities (e.g., hospitals, veterinarians,
X
pharmacies, poison centers)
Death certificates
X
Hospital discharge or outpatient records
X
Extracts from electronic medical records
X
Telephone survey
School-based survey
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Council of State and Territorial Epidemiologists
Position Statement Template: Standardized Surveillance for Diseases or Conditions, Revised 2014
Other _________________________
4. Utilize standardized criteria for case identification and classification (Sections VI and VII) for case
ascertainment for Arboviral Diseases and add case ascertainment for Arboviral Diseases to the Nationally
Notifiable Condition List.
4a. Immediately notifiable, extremely urgent (within 4 hours)
4b. Immediately notifiable, urgent (within 24 hours)
4c. Routinely notifiable
CSTE recommends that all States and Territories enact laws (statute or rule/regulation as appropriate) to
make this disease or condition reportable in their jurisdiction. Jurisdictions (e.g. States and Territories)
conducting surveillance (according to these methods) should submit case notifications** to CDC.
5. CDC should publish data on case ascertainment for Arboviral Diseases as appropriate in MMWR and
other venues (see Section IX).
CSTE recommends that all jurisdictions (e.g. States or Territories) with legal authority to conduct public
health surveillance follow the recommended methods as outlined above.
Terminology:
* Reporting: process of a healthcare provider or other entity submitting a report (case information) of a condition under public health
surveillance TO local or state public health.
**Notification: process of a local or state public health authority submitting a report (case information) of a condition on the Nationally
Notifiable Condition List TO CDC.
IV. Goals of Surveillance
To provide information on the temporal, geographic, and demographic occurrence of arboviral diseases to
facilitate prevention and control for these vector-borne infections.
V. Methods for Surveillance: Surveillance for Arboviral neuroinvasive and non-neuroinvasive diseases
should use the recommended sources of data and the extent of coverage listed in Table III.
VI. Criteria for case identification
A. Narrative: A description of suggested criteria for case ascertainment of a specific condition.
Report any illness to public health authorities that meets any of the following criteria.
●
Any person with laboratory evidence of recent arboviral infection as indicated by:
o Isolation of arbovirus from, or demonstration of specific arbovirus antigen or nucleic acid
in, tissue, blood, cerebrospinal fluid (CSF), or other body fluid
o Four-fold or greater change in arbovirus-specific quantitative antibody titers in paired sera
o Arbovirus-specific immunoglobulin M (IgM) antibodies in CSF or serum
●
A person whose healthcare record contains a diagnosis of an arboviral infection
●
A person whose death certificate lists an arboviral infection as a cause of death or a significant
condition contributing to death
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Council of State and Territorial Epidemiologists
Position Statement Template: Standardized Surveillance for Diseases or Conditions, Revised 2014
B. Table of criteria to determine whether a case should be reported to public health authorities
Table VI-B.Table of criteria to determine whether a case should be reported to public health
authorities.
Criterion
Arboviral
Arboviral NonNeuroinvasive
neuroinvasive Disease
Disease
Clinical Evidence
Healthcare record contains a diagnosis of arboviral
S
S
infection
Death certificate lists arboviral disease as a cause of death
S
S
or a significant condition contributing to death
Laboratory Evidence
Isolation of arbovirus from, or demonstration of arbovirusS
S
specific antigen or nucleic acid in, tissue, blood, CSF, or
other body fluid
Four-fold or greater change in arbovirus-specific
S
S
quantitative antibody titers in paired sera
Arbovirus-specific immunoglobulin M (IgM) antibodies in
S
S
CSF or serum
Notes:
S = This criterion alone is Sufficient to report a case.
N = All “N” criteria in the same column are Necessary to report a case.
O = At least one of these “O” (Optional) criteria in each category (e.g., clinical evidence and laboratory
evidence) in the same column—in conjunction with all “N” criteria in the same column—is required to
report a case.
* A requisition or order for any of the “S” laboratory tests is sufficient to meet the reporting criteria.
C. Disease-specific data elements
Clinical Information
Underlying chronic illness
Immune suppression
Blood transfusion in past 30 days
Blood donation in past 30 days
Organ transplant recipient in past 30 days
Organ donor
Pregnant
Prenatal exposure
Breast fed
Laboratory exposure
Hospitalized
Fatality
Epidemiologic Risk Factors
Occupation
Travel in 5-15 days prior to onset of illness
County and State where infection was presumably contracted
Mosquito exposure
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Council of State and Territorial Epidemiologists
Position Statement Template: Standardized Surveillance for Diseases or Conditions, Revised 2014
VII. Case Definition for Case Classification
A. Narrative: Description of criteria to determine how a case should be classified.
Arboviruses-which include but are not limited to:
● California serogroup viruses (California encephalitis, Jamestown Canyon, Keystone, La Crosse,
Snowshoe hare, and Trivittatus viruses)
● Eastern equine encephalitis virus
● Powassan virus
● St. Louis encephalitis virus
● West Nile virus
● Western equine encephalitis virus
● Chikungunya virus
Background
Arthropod-borne viruses (arboviruses) are transmitted to humans primarily through the bites of infected
mosquitoes, ticks, sand flies, or midges. Other modes of transmission for some arboviruses include blood
transfusion, organ transplantation, perinatal transmission, breast feeding, and laboratory exposures.
More than 130 arboviruses are known to cause human disease. Most arboviruses of public health
importance belong to one of three virus genera: Flavivirus, Alphavirus, and Orthobunyavirus.
Clinical Description
Most arboviral infections are asymptomatic. Clinical disease ranges from mild febrile illness to severe
encephalitis. For the purpose of surveillance and reporting, based on their clinical presentation, arboviral
disease cases are often categorized into two primary groups: neuroinvasive disease and nonneuroinvasive disease.
Neuroinvasive disease
Many arboviruses cause neuroinvasive disease such as aseptic meningitis, encephalitis, or acute flaccid
paralysis (AFP). These illnesses are usually characterized by the acute onset of fever with headache,
myalgia, stiff neck, altered mental status, seizures, limb weakness, or CSF pleocytosis. AFP may result
from anterior myelitis, peripheral neuritis, or post-infectious peripheral demyelinating neuropathy (i.e.,
Guillain-Barre’ syndrome). Less common neurological manifestations, such as cranial nerve palsies, also
occur.
Non-neuroinvasive disease
Most arboviruses are capable of causing an acute systemic febrile illness (e.g., West Nile fever) that may
include headache, myalgia, arthralgia, rash, or gastrointestinal symptoms. Some viruses also can cause
more characteristic clinical manifestations, such as severe polyarthralgia or arthritis due to Chikungunya
virus or other alphaviruses (e.g., Mayaro, Ross River, O’nyong-nyong).
Clinical Criteria
A clinically compatible case of arboviral disease is defined as follows:
Neuroinvasive disease
● Meningitis, encephalitis, acute flaccid paralysis, or other acute signs of central or peripheral
neurologic dysfunction, as documented by a physician, AND
● Absence of a more likely clinical explanation. Other clinically compatible symptoms of arbovirus
disease include: headache, myalgia, rash, arthralgia, vertigo, vomiting, paresis and/ or nuchal
rigidity.
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Council of State and Territorial Epidemiologists
Position Statement Template: Standardized Surveillance for Diseases or Conditions, Revised 2014
Non-neuroinvasive disease
● Fever (chills) as reported by the patient or a health-care provider, AND
● Absence of neuroinvasive disease, AND
● Absence of a more likely clinical explanation. Other clinically compatible symptoms of arbovirus
disease include: headache, myalgia, rash, arthralgia, vertigo, vomiting, paresis and/ or nuchal
rigidity.
Laboratory Criteria
● Isolation of virus from, or demonstration of specific viral antigen or nucleic acid in, tissue, blood,
CSF, or other body fluid, OR
● Four-fold or greater change in virus-specific quantitative antibody titers in paired sera, OR
● Virus-specific IgM antibodies in serum with confirmatory virus-specific neutralizing antibodies in
the same or a later specimen, OR
● Virus-specific IgM antibodies in CSF or serum.
Case classification
Confirmed:
Neuroinvasive disease
A case that meets the above clinical criteria for neuroinvasive disease and one or more of the following
laboratory criteria for a confirmed case:
● Isolation of virus from, or demonstration of specific viral antigen or nucleic acid in, tissue, blood,
CSF, or other body fluid, OR
● Four-fold or greater change in virus-specific quantitative antibody titers in paired sera, OR
● Virus-specific IgM antibodies in serum with confirmatory virus-specific neutralizing antibodies in
the same or a later specimen, OR
● Virus-specific IgM antibodies in CSF, with our without a reported pleocytosis, and a negative result
for other IgM antibodies in CSF for arboviruses endemic to the region where exposure occurred.
Non-neuroinvasive disease
A case that meets the above clinical criteria for non-neuroinvasive disease and one or more of the
following laboratory criteria for a confirmed case:
● Isolation of virus from, or demonstration of specific viral antigen or nucleic acid in, tissue, blood, or
other body fluid, excluding CSF, OR
● Four-fold or greater change in virus-specific quantitative antibody titers in paired sera, OR
● Virus-specific IgM antibodies in serum with confirmatory virus-specific neutralizing antibodies in
the same or a later specimen.
Probable
Neuroinvasive disease
A case that meets the above clinical criteria for neuroinvasive disease and the following laboratory criteria:
● Virus-specific IgM antibodies in CSF or serum but with no other testing.
Non-neuroinvasive disease
A case that meets the above clinical criteria for non-neuroinvasive disease and the laboratory criteria for a
probable case:
● Virus-specific IgM antibodies in serum but with no other testing.
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Council of State and Territorial Epidemiologists
Position Statement Template: Standardized Surveillance for Diseases or Conditions, Revised 2014
B. Classification Tables
Table VII-B.Criteria for defining a case of Arboviral Disease.
Criterion
Clinical Evidence
Fever (chills)
Headache
Myalgia
Rash
Arthralgia
Vertigo
Vomiting
Paresis
Nuchal rigidity
Neurologic illness
Aseptic meningitis
Encephalitis
Myelitis
Disorientation
Obtundation
Peripheral demyelinating
neuropathy
Acute Flaccid Paralysis
Nerve palsies
Peripheral neuritis
Sensory deficit
Abnormal reflexes
Seizures
Absence of a more likely clinical
explanation for the illness
Laboratory evidence
CSF pleocytosis
Isolation of arbovirus from
tissue, blood, or other body fluid,
excluding CSF
Demonstration of specific viral
antigen in tissue, blood, or other
body fluid, excluding CSF
Demonstration of nucleic acid in
tissue, blood, or other body fluid,
excluding CSF
Isolation of arbovirus in CSF
Demonstration of specific viral
antigen or nucleic acid in CSF
Four-fold or greater change in
virus-specific quantitative
antibody titers in paired sera
Neuroinvasive
Confirmed
Probable
Non-neuroinvasive
Confirmed
Probable
O
O
O
O
O
O
O
O
O
N
O
O
O
O
O
O
O
O
O
O
O
O
O
O
N
O
O
O
O
O
N
O
O
O
O
O
O
O
O
A
A
A
A
A
A
N
O
O
O
O
O
O
O
O
A
A
A
A
A
A
O
O
O
O
O
O
O
O
O
O
O
O
O
O
A
A
A
A
A
A
A
A
A
A
A
A
A
A
N
N
N
N
O
O
A
A
O
O
A
A
O
O
A
A
O
A
O
A
O
A
A
A
O
A
A
A
O
A
O
A
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Council of State and Territorial Epidemiologists
Position Statement Template: Standardized Surveillance for Diseases or Conditions, Revised 2014
Arbovirus-specific IgM
antibodies in serum with
confirmatory virus-specific
neutralizing antibodies in same
or later specimen
O
A
O
A
Arbovirus-specific IgM
antibodies in CSF and a
negative result for IgM
antibodies in CSF for other
arboviruses in the same virus
O
A
A
A
family endemic to the region
where exposure occurred
Arbovirus-specific IgM
antibodies in CSF but with no
A
O
A
A
other testing
Arbovirus-specific IgM
antibodies in serum but with no
A
O
A
N
other testing
Criteria to distinguish a new
case:
Not counted as a new case if
previously classified as a case,
e.g., previously documented to
N
N
N
N
have virus-specific IgM
antibodies in CSF or serum
Notes:
S = This criterion alone is Sufficient to classify a case.
N = All “N” criteria in the same column are Necessary to classify a case. A number following an “N”
indicates that this criterion is only required for a specific disease/condition subtype (see below).
A = This criterion must be absent (i.e., NOT present) for the case to meet the classification criteria.
O = At least one of these “O” (Optional) criteria in each category (e.g., clinical evidence and laboratory
evidence) in the same column—in conjunction with all “N” criteria in the same column—is required to
classify a case. (These optional criteria are alternatives, which mean that a single column will have either
no O criteria or multiple O criteria; no column should have only one O.) A number following an “O”
indicates that this criterion is only required for a specific disease/condition subtype.
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Council of State and Territorial Epidemiologists
Position Statement Template: Standardized Surveillance for Diseases or Conditions, Revised 2014
VIII. Period of Surveillance
Surveillance should be ongoing.
IX. Data sharing/release and print criteria.
● Notification to CDC of confirmed and probable cases of arboviral diseases is recommended.
● CDC Division of Vector-Borne Diseases (DVBD) staff review, analyze, and summarize the national
data weekly. Provisional state-specific arboviral disease case counts are provided weekly in the
MMWR nationally notifiable diseases tables. Tables and maps are also provided on the CDC
DVBD and U.S. Geologic Survey (USGS) websites. These provisional data are used to: 1) Monitor
the epidemiology and geographic spread of arboviral diseases; 2) Provide timely information
regarding regional and national trends in arboviral diseases to public health officials and others;
and 3) Identify geographic areas where additional prevention and control efforts may be needed.
In circumstances where there is a potential for an international health impact, data from these
notifications may be shared with international partners (e.g., PHAC, ECDC, WHO, PAHO).
● Final data are published annually in the MMWR Summary of Notifiable Diseases, posted on the
CDC DVBD website, and presented or published at scientific meetings and in peer-reviewed
literature. Additional tables and limited use datasets are available to researchers, pharmaceutical
companies, media, and the general public upon request to the CDC DVBD. These final data are
used to: 1) Monitor the epidemiology, incidence, and geographic spread of arboviral diseases; 2)
Identify geographic areas in which it may be appropriate to conduct analytic studies of control
methods, risk factors, disease severity, or other public health aspects; and 3) Evaluate arboviral
disease funding needs and allocate resources.
● All cases are verified with the state health departments before publication. Individual case
notifications are made to state and local health departments depending on circumstances. For
example, viremic blood donors or transplant or transfusion-associated cases require rapid
notification and investigation.
● To facilitate access to ArboNET data while maintaining patient confidentiality, and to ensure that
users understand the limitations of the data, the CDC Arboviral Diseases Branch has developed
data sharing and release guidelines, a data request form, and a data use agreement. These
policies and procedures are consistent with those developed by CDC and the CSTE for the
release and sharing of data reported to the Nationally Notifiable Diseases Surveillance System
(NNDSS).
X. References
XI. Coordination
Agencies for Response
(1)
Thomas R. Frieden, MD, MPH
Centers for Disease Control and Prevention
Director
1600 Clifton Road, NE
Atlanta, GA 30333
(404) 639-7000
txf2@cdc.gov
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Council of State and Territorial Epidemiologists
Position Statement Template: Standardized Surveillance for Diseases or Conditions, Revised 2014
XII. Submitting Author:
(1)
Carina Blackmore, DVM, Ph.D.
Deputy State Epidemiologist and State Public Health Veterinarian
Florida Department of Health
4052 Bald Cypress Way, Bin A-09
Tallahassee, FL 32330
(850) 245-4732
Carina.Blackmore@FLHealth.gov
Co-Author:
(1)
Kristy K. Bradley, DVM, MPH
State Epidemiologist and State Public Health Veterinarian
Oklahoma State Department of Health
1000 NE Tenth Street Room 606
Oklahoma City, OK 73117
405-271-7637
kristyb@health.ok.gov
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Council of State and Territorial Epidemiologists
Position Statement Template: Standardized Surveillance for Diseases or Conditions, Revised 2014